procps/fuser.c - busybox - Git at Google

 /* vi: set sw=4 ts=4: */
 /*
  * tiny fuser implementation
  *
  * Copyright 2004 Tony J. White
  *
  * Licensed under GPLv2, see file LICENSE in this source tree.
  */
 //config:config FUSER
 //config:	bool "fuser (7 kb)"
 //config:	default y
 //config:	help
 //config:	fuser lists all PIDs (Process IDs) that currently have a given
 //config:	file open. fuser can also list all PIDs that have a given network
 //config:	(TCP or UDP) port open.

 //applet:IF_FUSER(APPLET(fuser, BB_DIR_USR_BIN, BB_SUID_DROP))

 //kbuild:lib-$(CONFIG_FUSER) += fuser.o

 //usage:#define fuser_trivial_usage
 //usage:       "[OPTIONS] FILE or PORT/PROTO"
 //usage:#define fuser_full_usage "\n\n"
 //usage:       "Find processes which use FILEs or PORTs\n"
 //usage:     "\n	-m	Find processes which use same fs as FILEs"
 //usage:     "\n	-4,-6	Search only IPv4/IPv6 space"
 //usage:     "\n	-s	Don't display PIDs"
 //usage:     "\n	-k	Kill found processes"
 //usage:     "\n	-SIGNAL	Signal to send (default: KILL)"

 #include "libbb.h"
 #include "common_bufsiz.h"

 #define MAX_LINE 255

 #define OPTION_STRING "mks64"
 enum {
 	OPT_MOUNT  = (1 << 0),
 	OPT_KILL   = (1 << 1),
 	OPT_SILENT = (1 << 2),
 	OPT_IP6    = (1 << 3),
 	OPT_IP4    = (1 << 4),
 };

 typedef struct inode_list {
 	struct inode_list *next;
 	ino_t inode;
 	dev_t dev;
 } inode_list;

 struct globals {
 	int recursion_depth;
 	pid_t mypid;
 	inode_list *inode_list_head;
 	smallint kill_failed;
 	int killsig;
 } FIX_ALIASING;
 #define G (*(struct globals*)bb_common_bufsiz1)
 #define INIT_G() do { \
 	setup_common_bufsiz(); \
 	G.mypid = getpid(); \
 	G.killsig = SIGKILL; \
 } while (0)

 static void add_inode(const struct stat *st)
 {
 	inode_list **curr = &G.inode_list_head;

 	while (*curr) {
 		if ((*curr)->dev == st->st_dev
 		 && (*curr)->inode == st->st_ino
 		) {
 			return;
 		}
 		curr = &(*curr)->next;
 	}

 	*curr = xzalloc(sizeof(inode_list));
 	(*curr)->dev = st->st_dev;
 	(*curr)->inode = st->st_ino;
 }

 static smallint search_dev_inode(const struct stat *st)
 {
 	inode_list *ilist = G.inode_list_head;

 	while (ilist) {
 		if (ilist->dev == st->st_dev) {
 			if (option_mask32 & OPT_MOUNT)
 				return 1;
 			if (ilist->inode == st->st_ino)
 				return 1;
 		}
 		ilist = ilist->next;
 	}
 	return 0;
 }

 enum {
 	PROC_NET = 0,
 	PROC_DIR,
 	PROC_DIR_LINKS,
 	PROC_SUBDIR_LINKS,
 };

 static smallint scan_proc_net_or_maps(const char *path, unsigned port)
 {
 	FILE *f;
 	char line[MAX_LINE + 1], addr[68];
 	int major, minor, r;
 	long long uint64_inode;
 	unsigned tmp_port;
 	smallint retval;
 	struct stat statbuf;
 	const char *fmt;
 	void *fag, *sag;

 	f = fopen_for_read(path);
 	if (!f)
 		return 0;

 	if (G.recursion_depth == PROC_NET) {
 		int fd;

 		/* find socket dev */
 		statbuf.st_dev = 0;
 		fd = socket(AF_INET, SOCK_DGRAM, 0);
 		if (fd >= 0) {
 			fstat(fd, &statbuf);
 			close(fd);
 		}

 		fmt = "%*d: %64[0-9A-Fa-f]:%x %*x:%*x %*x "
 			"%*x:%*x %*x:%*x %*x %*d %*d %llu";
 		fag = addr;
 		sag = &tmp_port;
 	} else {
 		fmt = "%*s %*s %*s %x:%x %llu";
 		fag = &major;
 		sag = &minor;
 	}

 	retval = 0;
 	while (fgets(line, MAX_LINE, f)) {
 		r = sscanf(line, fmt, fag, sag, &uint64_inode);
 		if (r != 3)
 			continue;

 		statbuf.st_ino = uint64_inode;
 		if (G.recursion_depth == PROC_NET) {
 			r = strlen(addr);
 			if (r == 8 && (option_mask32 & OPT_IP6))
 				continue;
 			if (r > 8 && (option_mask32 & OPT_IP4))
 				continue;
 			if (tmp_port == port)
 				add_inode(&statbuf);
 		} else {
 			if (major != 0 && minor != 0 && statbuf.st_ino != 0) {
 				statbuf.st_dev = makedev(major, minor);
 				retval = search_dev_inode(&statbuf);
 				if (retval)
 					break;
 			}
 		}
 	}
 	fclose(f);

 	return retval;
 }

 static smallint scan_recursive(const char *path)
 {
 	DIR *d;
 	struct dirent *d_ent;
 	smallint stop_scan;
 	smallint retval;

 	d = opendir(path);
 	if (d == NULL)
 		return 0;

 	G.recursion_depth++;
 	retval = 0;
 	stop_scan = 0;
 	while (!stop_scan && (d_ent = readdir(d)) != NULL) {
 		struct stat statbuf;
 		pid_t pid;
 		char *subpath;

 		subpath = concat_subpath_file(path, d_ent->d_name);
 		if (subpath == NULL)
 			continue; /* . or .. */

 		switch (G.recursion_depth) {
 		case PROC_DIR:
 			pid = (pid_t)bb_strtou(d_ent->d_name, NULL, 10);
 			if (errno != 0
 			 || pid == G.mypid
 			/* "this PID doesn't use specified FILEs or PORT/PROTO": */
 			 || scan_recursive(subpath) == 0
 			) {
 				break;
 			}
 			if (option_mask32 & OPT_KILL) {
 				if (kill(pid, G.killsig) != 0) {
 					bb_perror_msg("kill pid %s", d_ent->d_name);
 					G.kill_failed = 1;
 				}
 			}
 			if (!(option_mask32 & OPT_SILENT))
 				printf("%s ", d_ent->d_name);
 			retval = 1;
 			break;

 		case PROC_DIR_LINKS:
 			switch (
 				index_in_substrings(
 					"cwd"  "\0" "exe"  "\0"
 					"root" "\0" "fd"   "\0"
 					"lib"  "\0" "mmap" "\0"
 					"maps" "\0",
 					d_ent->d_name
 				)
 			) {
 			enum {
 				CWD_LINK,
 				EXE_LINK,
 				ROOT_LINK,
 				FD_DIR_LINKS,
 				LIB_DIR_LINKS,
 				MMAP_DIR_LINKS,
 				MAPS,
 			};
 			case CWD_LINK:
 			case EXE_LINK:
 			case ROOT_LINK:
 				goto scan_link;
 			case FD_DIR_LINKS:
 			case LIB_DIR_LINKS:
 			case MMAP_DIR_LINKS:
 				stop_scan = scan_recursive(subpath);
 				if (stop_scan)
 					retval = stop_scan;
 				break;
 			case MAPS:
 				stop_scan = scan_proc_net_or_maps(subpath, 0);
 				if (stop_scan)
 					retval = stop_scan;
 			default:
 				break;
 			}
 			break;
 		case PROC_SUBDIR_LINKS:
   scan_link:
 			if (stat(subpath, &statbuf) < 0)
 				break;
 			stop_scan = search_dev_inode(&statbuf);
 			if (stop_scan)
 				retval = stop_scan;
 		default:
 			break;
 		}
 		free(subpath);
 	}
 	closedir(d);
 	G.recursion_depth--;
 	return retval;
 }

 int fuser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int fuser_main(int argc UNUSED_PARAM, char **argv)
 {
 	char **pp;

 	INIT_G();

 	/* Handle -SIGNAL. Oh my... */
 	pp = argv;
 	while (*++pp) {
 		int sig;
 		char *arg = *pp;

 		if (arg[0] != '-')
 			continue;
 		if (arg[1] == '-' && arg[2] == '\0') /* "--" */
 			break;
 		if ((arg[1] == '4' || arg[1] == '6') && arg[2] == '\0')
 			continue; /* it's "-4" or "-6" */
 		sig = get_signum(&arg[1]);
 		if (sig < 0)
 			continue;
 		/* "-SIGNAL" option found. Remove it and bail out */
 		G.killsig = sig;
 		do {
 			pp[0] = arg = pp[1];
 			pp++;
 		} while (arg);
 		break;
 	}

 	getopt32(argv, "^" OPTION_STRING "\0" "-1"/*at least one arg*/);
 	argv += optind;

 	pp = argv;
 	while (*pp) {
 		/* parse net arg */
 		unsigned port;
 		char path[sizeof("/proc/net/TCP6")];

 		strcpy(path, "/proc/net/");
 		if (sscanf(*pp, "%u/%4s", &port, path + sizeof("/proc/net/")-1) == 2
 		 && access(path, R_OK) == 0
 		) {
 			/* PORT/PROTO */
 			scan_proc_net_or_maps(path, port);
 		} else {
 			/* FILE */
 			struct stat statbuf;
 			xstat(*pp, &statbuf);
 			add_inode(&statbuf);
 		}
 		pp++;
 	}

 	if (scan_recursive("/proc")) {
 		if (!(option_mask32 & OPT_SILENT))
 			bb_putchar('\n');
 		return G.kill_failed;
 	}

 	return EXIT_FAILURE;
 }
	/* vi: set sw=4 ts=4: */
	/*
	* tiny fuser implementation
	*
	* Copyright 2004 Tony J. White
	*
	* Licensed under GPLv2, see file LICENSE in this source tree.
	*/
	//config:config FUSER
	//config: bool "fuser (7 kb)"
	//config: default y
	//config: help
	//config: fuser lists all PIDs (Process IDs) that currently have a given
	//config: file open. fuser can also list all PIDs that have a given network
	//config: (TCP or UDP) port open.

	//applet:IF_FUSER(APPLET(fuser, BB_DIR_USR_BIN, BB_SUID_DROP))

	//kbuild:lib-$(CONFIG_FUSER) += fuser.o

	//usage:#define fuser_trivial_usage
	//usage: "[OPTIONS] FILE or PORT/PROTO"
	//usage:#define fuser_full_usage "\n\n"
	//usage: "Find processes which use FILEs or PORTs\n"
	//usage: "\n -m Find processes which use same fs as FILEs"
	//usage: "\n -4,-6 Search only IPv4/IPv6 space"
	//usage: "\n -s Don't display PIDs"
	//usage: "\n -k Kill found processes"
	//usage: "\n -SIGNAL Signal to send (default: KILL)"

	#include "libbb.h"
	#include "common_bufsiz.h"

	#define MAX_LINE 255

	#define OPTION_STRING "mks64"
	enum {
	OPT_MOUNT = (1 << 0),
	OPT_KILL = (1 << 1),
	OPT_SILENT = (1 << 2),
	OPT_IP6 = (1 << 3),
	OPT_IP4 = (1 << 4),
	};

	typedef struct inode_list {
	struct inode_list *next;
	ino_t inode;
	dev_t dev;
	} inode_list;

	struct globals {
	int recursion_depth;
	pid_t mypid;
	inode_list *inode_list_head;
	smallint kill_failed;
	int killsig;
	} FIX_ALIASING;
	#define G ((struct globals)bb_common_bufsiz1)
	#define INIT_G() do { \
	setup_common_bufsiz(); \
	G.mypid = getpid(); \
	G.killsig = SIGKILL; \
	} while (0)

	static void add_inode(const struct stat *st)
	{
	inode_list **curr = &G.inode_list_head;

	while (*curr) {
	if ((*curr)->dev == st->st_dev
	&& (*curr)->inode == st->st_ino
	) {
	return;
	}
	curr = &(*curr)->next;
	}

	*curr = xzalloc(sizeof(inode_list));
	(*curr)->dev = st->st_dev;
	(*curr)->inode = st->st_ino;
	}

	static smallint search_dev_inode(const struct stat *st)
	{
	inode_list *ilist = G.inode_list_head;

	while (ilist) {
	if (ilist->dev == st->st_dev) {
	if (option_mask32 & OPT_MOUNT)
	return 1;
	if (ilist->inode == st->st_ino)
	return 1;
	}
	ilist = ilist->next;
	}
	return 0;
	}

	enum {
	PROC_NET = 0,
	PROC_DIR,
	PROC_DIR_LINKS,
	PROC_SUBDIR_LINKS,
	};

	static smallint scan_proc_net_or_maps(const char *path, unsigned port)
	{
	FILE *f;
	char line[MAX_LINE + 1], addr[68];
	int major, minor, r;
	long long uint64_inode;
	unsigned tmp_port;
	smallint retval;
	struct stat statbuf;
	const char *fmt;
	void fag, sag;

	f = fopen_for_read(path);
	if (!f)
	return 0;

	if (G.recursion_depth == PROC_NET) {
	int fd;

	/* find socket dev */
	statbuf.st_dev = 0;
	fd = socket(AF_INET, SOCK_DGRAM, 0);
	if (fd >= 0) {
	fstat(fd, &statbuf);
	close(fd);
	}

	fmt = "%d: %64[0-9A-Fa-f]:%x %x:%x %x "
	"%x:%x %x:%x %x %d %*d %llu";
	fag = addr;
	sag = &tmp_port;
	} else {
	fmt = "%s %s %*s %x:%x %llu";
	fag = &major;
	sag = &minor;
	}

	retval = 0;
	while (fgets(line, MAX_LINE, f)) {
	r = sscanf(line, fmt, fag, sag, &uint64_inode);
	if (r != 3)
	continue;

	statbuf.st_ino = uint64_inode;
	if (G.recursion_depth == PROC_NET) {
	r = strlen(addr);
	if (r == 8 && (option_mask32 & OPT_IP6))
	continue;
	if (r > 8 && (option_mask32 & OPT_IP4))
	continue;
	if (tmp_port == port)
	add_inode(&statbuf);
	} else {
	if (major != 0 && minor != 0 && statbuf.st_ino != 0) {
	statbuf.st_dev = makedev(major, minor);
	retval = search_dev_inode(&statbuf);
	if (retval)
	break;
	}
	}
	}
	fclose(f);

	return retval;
	}

	static smallint scan_recursive(const char *path)
	{
	DIR *d;
	struct dirent *d_ent;
	smallint stop_scan;
	smallint retval;

	d = opendir(path);
	if (d == NULL)
	return 0;

	G.recursion_depth++;
	retval = 0;
	stop_scan = 0;
	while (!stop_scan && (d_ent = readdir(d)) != NULL) {
	struct stat statbuf;
	pid_t pid;
	char *subpath;

	subpath = concat_subpath_file(path, d_ent->d_name);
	if (subpath == NULL)
	continue; /* . or .. */

	switch (G.recursion_depth) {
	case PROC_DIR:
	pid = (pid_t)bb_strtou(d_ent->d_name, NULL, 10);
	if (errno != 0
	\|\| pid == G.mypid
	/* "this PID doesn't use specified FILEs or PORT/PROTO": */
	\|\| scan_recursive(subpath) == 0
	) {
	break;
	}
	if (option_mask32 & OPT_KILL) {
	if (kill(pid, G.killsig) != 0) {
	bb_perror_msg("kill pid %s", d_ent->d_name);
	G.kill_failed = 1;
	}
	}
	if (!(option_mask32 & OPT_SILENT))
	printf("%s ", d_ent->d_name);
	retval = 1;
	break;

	case PROC_DIR_LINKS:
	switch (
	index_in_substrings(
	"cwd" "\0" "exe" "\0"
	"root" "\0" "fd" "\0"
	"lib" "\0" "mmap" "\0"
	"maps" "\0",
	d_ent->d_name
	)
	) {
	enum {
	CWD_LINK,
	EXE_LINK,
	ROOT_LINK,
	FD_DIR_LINKS,
	LIB_DIR_LINKS,
	MMAP_DIR_LINKS,
	MAPS,
	};
	case CWD_LINK:
	case EXE_LINK:
	case ROOT_LINK:
	goto scan_link;
	case FD_DIR_LINKS:
	case LIB_DIR_LINKS:
	case MMAP_DIR_LINKS:
	stop_scan = scan_recursive(subpath);
	if (stop_scan)
	retval = stop_scan;
	break;
	case MAPS:
	stop_scan = scan_proc_net_or_maps(subpath, 0);
	if (stop_scan)
	retval = stop_scan;
	default:
	break;
	}
	break;
	case PROC_SUBDIR_LINKS:
	scan_link:
	if (stat(subpath, &statbuf) < 0)
	break;
	stop_scan = search_dev_inode(&statbuf);
	if (stop_scan)
	retval = stop_scan;
	default:
	break;
	}
	free(subpath);
	}
	closedir(d);
	G.recursion_depth--;
	return retval;
	}

	int fuser_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
	int fuser_main(int argc UNUSED_PARAM, char **argv)
	{
	char **pp;

	INIT_G();

	/* Handle -SIGNAL. Oh my... */
	pp = argv;
	while (*++pp) {
	int sig;
	char arg = pp;

	if (arg[0] != '-')
	continue;
	if (arg[1] == '-' && arg[2] == '\0') /* "--" */
	break;
	if ((arg[1] == '4' \|\| arg[1] == '6') && arg[2] == '\0')
	continue; /* it's "-4" or "-6" */
	sig = get_signum(&arg[1]);
	if (sig < 0)
	continue;
	/* "-SIGNAL" option found. Remove it and bail out */
	G.killsig = sig;
	do {
	pp[0] = arg = pp[1];
	pp++;
	} while (arg);
	break;
	}

	getopt32(argv, "^" OPTION_STRING "\0" "-1"/at least one arg/);
	argv += optind;

	pp = argv;
	while (*pp) {
	/* parse net arg */
	unsigned port;
	char path[sizeof("/proc/net/TCP6")];

	strcpy(path, "/proc/net/");
	if (sscanf(*pp, "%u/%4s", &port, path + sizeof("/proc/net/")-1) == 2
	&& access(path, R_OK) == 0
	) {
	/* PORT/PROTO */
	scan_proc_net_or_maps(path, port);
	} else {
	/* FILE */
	struct stat statbuf;
	xstat(*pp, &statbuf);
	add_inode(&statbuf);
	}
	pp++;
	}

	if (scan_recursive("/proc")) {
	if (!(option_mask32 & OPT_SILENT))
	bb_putchar('\n');
	return G.kill_failed;
	}

	return EXIT_FAILURE;
	}